Image of the new most distant quasar ULAS J1120+0641. The quasar is the
red dot near the centre of the image (marked with lines). The picture is a color composite made from images taken with the Liverpool Telescope and the United Kingdom Infrared Telescope. The quasar lies in the constellation Leo, a few degrees from the bright galaxy Messier 66.
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Although no light is emitted by the black hole itself, its strong gravity
pulls in surrounding gas that is heated up and shines as what astronomers
call a quasar. The existence of such a massive black hole so soon after
the Big Bang presents a challenge to theories that attempt to describe the
formation of galaxies.

The quasar, known as ULAS J1120+0641 based on its location in the sky, was
originally identified in images of the sky taken by the United Kingdom
Infrared Telescope (UKIRT) as part of the UKIRT Infrared Deep Sky Survey
(UKIDSS). UKIDSS has observed approximately 5% of the sky and the team
select quasar candidates based on their colours in the survey. These
candidates are then followed up with the Liverpool Telescope to weed out
contaminants.

"Distant quasars have very distinctive colours in the UKIDSS data that
allow them to be identified," says LJMU's Dr Chris Simpson, who leads this
part of the project. "Unfortunately, these colours are also shared by cool
stars in our own galaxy and we need additional images in visible light to
tell them apart. It is the ability to schedule such observations with the
Liverpool Telescope as soon as a candidate has been found in the UKIDSS
data that makes it such a vital part of this process."

"This is an exciting result as this quasar provides a unique luminous
beacon in the early universe," says Dr Daniel Mortlock of Imperial
College, London, lead author of the study. "It is much brighter than
anything else at this distance and we can use it to study what conditions
were like in the early universe."